VOA标准英语2011--Coastal Trees Help Fight Global Warming

Coastal¹ Trees Help Fight Global Warming

A new study says the world's tropical coastal forests store more planet-warming carbon dioxide than almost any other ecosystem².
But rapid loss of these forests - known as mangroves - is releasing substantial and previously⁴ unrecognized quantities of greenhouse gases into the atmosphere.
Mangroves provide rich breeding grounds for fish, and they help buffer⁵ coastal areas from storm surges. But their role in trapping climate-warming carbon dioxide has not been studied much.
A new study in the journal "Nature Geoscience" provides a first look.
More carbon per hectare than tropical rainforests
Daniel Donato with the Forest Service of the U.S. Department of Agriculture and his colleagues surveyed tree mass, dead wood, and soil carbon in 25 mangrove³ ecosystems⁶ around the tropical Indian and Pacific Oceans.
Daniel Donato
A mangrove landscape on the Ganges River Delta⁷, Bangladesh. Mangroves are being rapidly deforested globally.
Donato says study shows, "They are right up there with the most carbon-rich forests in the world."
Donato's results showed mangroves store about three to four times more carbon per hectare as temperate⁸ forests or even tropical rainforests. But Donato says most of it is hidden.
"Carbon in mangroves is really about the below-ground story," he says. "Most of the carbon stored in that ecosystem is in the soil and the tree roots."
Mangroves stored about five times as much carbon in deep soils compared to temperate or tropical forests.
Rapid loss
But the researchers note that a third to a half of the world's mangroves have been cut down in the last half-century for timber, coastal development and aquaculture.
The researchers estimate that the amount of greenhouse gases released each year from mangrove deforestation may be equivalent to as much as 10 percent of the global toll⁹ from deforestation.That's despite the fact that mangroves make up less than 1 percent of the tropical forest area.
Donato says the research should get the attention of policymakers."It shows mangroves are probably pretty good candidates for things like carbon-market trading to encourage sustainable forest management."
Dollar value
Carbon markets, where industries buy the right to emit carbon dioxide in exchange for protecting forests or other offsets¹⁰, could be a powerful force for conservation, environmentalists say.
Many developing countries, especially in Asia, are clearing mangroves for fish and shrimp¹¹ aquaculture because it can be profitable. The value of the mangrove often is not immediately obvious to policymakers, says Emily Pidgeon, director the marine¹² climate change program at the environmental group Conservation International.
"By suddenly having an actual mechanism¹³ to value these systems in dollars, it gives you a potentially very large new mechanism for countering the other financial and economic arguments," she says.
Consumer standards
Other groups are approaching the economics of mangrove conservation from the buyer's side. They are encouraging Western supermarkets and other large consumers to only buy farmed seafood¹⁴ that meets certain standards, including limited impact on mangrove loss.
Pidgeon says it works well in some places. But other developing countries are not equipped to meet or enforce the standards.
"The government structures are not very strong," she says, "and the expertise¹⁵ and capacity to apply some of these approaches is often very challenging."
Mosaic¹⁶ of services
One of the most important ways to help local communities value the mangroves, Pidgeon says, is to see them as part of a mosaic that provides a whole range of services, including nurturing¹⁷ the fisheries that many developing-world coastal fishing communities depend on for their livelihoods¹⁸.
"Although you may catch your fish in one particular piece of the mosaic, the fish are only there to catch because of the time they spend in all the other pieces," she adds.
For many coastal communities, carbon storage is just the latest service they may see mangroves providing.

1 coastal   

adj.海岸的，沿海的，沿岸的

参考例句：

• The ocean waves are slowly eating away the coastal rocks.大海的波浪慢慢地侵蚀着岸边的岩石。
• This country will fortify the coastal areas.该国将加强沿海地区的防御。

2 ecosystem   

n.生态系统

参考例句：

• This destroyed the ecosystem of the island.这样破坏了岛上的生态系统。
• We all have an interest in maintaining the integrity of the ecosystem.维持生态系统的完整是我们共同的利益。

3 mangrove   

n.(植物)红树，红树林

参考例句：

• It is the world's largest tidal mangrove forest.它是世界上最大的红树林沼泽地。
• Many consider this the most beautiful mangrove forest in all Thailand.许多人认为这里是全泰国最美丽的红树林了。

4 previously   

adv.以前，先前（地）

参考例句：

• The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
• Let me digress for a moment and explain what had happened previously.让我岔开一会儿，解释原先发生了什么。

5 buffer   

n.起缓冲作用的人(或物)，缓冲器；vt.缓冲

参考例句：

• A little money can be a useful buffer in time of need.在急需时，很少一点钱就能解燃眉之急。
• Romantic love will buffer you against life's hardships.浪漫的爱会减轻生活的艰辛。

6 ecosystems   

n.生态系统( ecosystem的名词复数 )

参考例句：

• There are highly sensitive and delicately balanced ecosystems in the forest. 森林里有高度敏感、灵敏平衡的各种生态系统。 来自《简明英汉词典》
• Madagascar's ecosystems range from rainforest to semi-desert. 马达加斯加生态系统类型多样，从雨林到半荒漠等不一而足。 来自辞典例句

7 delta   

n.（流的）角洲

参考例句：

• He has been to the delta of the Nile.他曾去过尼罗河三角洲。
• The Nile divides at its mouth and forms a delta.尼罗河在河口分岔，形成了一个三角洲。

8 temperate   

adj.温和的，温带的，自我克制的，不过分的

参考例句：

• Asia extends across the frigid,temperate and tropical zones.亚洲地跨寒、温、热三带。
• Great Britain has a temperate climate.英国气候温和。

9 toll   

n.过路(桥)费；损失，伤亡人数；v.敲(钟)

参考例句：

• The hailstone took a heavy toll of the crops in our village last night.昨晚那场冰雹损坏了我们村的庄稼。
• The war took a heavy toll of human life.这次战争夺去了许多人的生命。

10 offsets   

n.开端( offset的名词复数 )；出发v.抵消( offset的第三人称单数 )；补偿；（为了比较的目的而）把…并列（或并置）；为（管道等）装支管

参考例句：

• The following paragraphs deal with intra-source offsets and the so-called \"bubble\" concept. 下面讨论污染源内部的补偿和所谓的“泡泡”概念。 来自英汉非文学 - 环境法 - 环境法
• The preceding paragraphs were concerned with inter-source offsets. 前文牵涉到污染源之间的补偿。 来自英汉非文学 - 环境法 - 环境法

11 shrimp   

n.虾，小虾；矮小的人

参考例句：

• When the shrimp farm is built it will block the stream.一旦养虾场建起来，将会截断这条河流。
• When it comes to seafood,I like shrimp the best.说到海鲜，我最喜欢虾。

12 marine   

adj.海的；海生的；航海的；海事的；n.水兵

参考例句：

• Marine creatures are those which live in the sea. 海洋生物是生存在海里的生物。
• When the war broke out,he volunteered for the Marine Corps.战争爆发时，他自愿参加了海军陆战队。

13 mechanism   

n.机械装置；机构，结构

参考例句：

• The bones and muscles are parts of the mechanism of the body.骨骼和肌肉是人体的组成部件。
• The mechanism of the machine is very complicated.这台机器的结构是非常复杂的。

14 seafood   

n.海产食品，海味，海鲜

参考例句：

• There's an excellent seafood restaurant near here.离这儿不远有家非常不错的海鲜馆。
• Shrimps are a popular type of seafood.小虾是比较普遍的一种海味。

15 expertise   

n.专门知识(或技能等)，专长

参考例句：

• We were amazed at his expertise on the ski slopes.他斜坡滑雪的技能使我们赞叹不已。
• You really have the technical expertise in a new breakthrough.让你真正在专业技术上有一个全新的突破。

16 mosaic   

n./adj.镶嵌细工的，镶嵌工艺品的，嵌花式的

参考例句：

• The sky this morning is a mosaic of blue and white.今天早上的天空是幅蓝白相间的画面。
• The image mosaic is a troublesome work.图象镶嵌是个麻烦的工作。

17 nurturing   

养育( nurture的现在分词 )； 培育； 滋长； 助长

参考例句：

• These delicate plants need careful nurturing. 这些幼嫩的植物需要精心培育。
• The modern conservatory is not an environment for nurturing plants. 这个现代化温室的环境不适合培育植物。

18 livelihoods   

生计，谋生之道( livelihood的名词复数 )

参考例句：

• First came the earliest individualistic pioneers who depended on hunting and fishing for their livelihoods. 走在最前面的是早期的个人主义先驱者，他们靠狩猎捕鱼为生。 来自英汉非文学 - 政府文件
• With little influence over policies, their traditional livelihoods are threatened. 因为马赛族人对政策的影响力太小，他们的传统生计受到了威胁。